From 106b4a2a78b2a2f14885604891957b84bba502db Mon Sep 17 00:00:00 2001 From: Adrian Betschart Date: Fri, 11 Sep 2026 17:13:14 +0200 Subject: drm/amd/display: Try RGB before YCbCr 4:4:4 in stream validation amdgpu_dm_create_validate_stream_for_sink() walks encoding_order[] and uses the first encoding that validates. YCbCr 4:4:4 is listed before RGB, so an HDMI sink that advertises 4:4:4 gets YCbCr 4:4:4 whenever the "color format" property is left at AUTO, even though RGB fits the same link. That contradicts the documented AUTO behaviour for HDMI in enum drm_connector_color_format (RGB, falling back to YCbCr 4:2:0 only when the bandwidth is not available or the mode is 4:2:0-only), which the amdgpu implementation of the property also describes. It also leaves the "Broadcast RGB" property without effect on such sinks, since the quantization range it selects only applies to RGB output. Try RGB first. The mask still holds every encoding the sink supports, so a mode that cannot carry RGB falls back exactly as before. For reference, v7.2 picked RGB here unless YCbCr 4:4:4 was forced through debugfs, while earlier kernels picked YCbCr 4:4:4 for any HDMI sink that advertised it. Fixes: 0b0ff65d3ca1 ("drm/amd/display: Refactor stream validation") Suggested-by: Adolfo Rodrigues Assisted-by: Claude Code:claude-fable-5-1 Signed-off-by: Adrian Betschart Reviewed-by: Fangzhi Zuo Tested-by: Adolfo Rodrigues Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher (cherry picked from commit 7de432bc753133764dc40d37f9388da56de251e7) --- drivers/rtc/rtc-test.c | 201 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 201 insertions(+) create mode 100644 drivers/rtc/rtc-test.c (limited to 'drivers/rtc/rtc-test.c') diff --git a/drivers/rtc/rtc-test.c b/drivers/rtc/rtc-test.c new file mode 100644 index 000000000..94f995feb --- /dev/null +++ b/drivers/rtc/rtc-test.c @@ -0,0 +1,201 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * An RTC test device/driver + * Copyright (C) 2005 Tower Technologies + * Author: Alessandro Zummo + */ + +#include +#include +#include +#include + +#define MAX_RTC_TEST 3 + +struct rtc_test_data { + struct rtc_device *rtc; + time64_t offset; + struct timer_list alarm; + bool alarm_en; +}; + +static struct platform_device *pdev[MAX_RTC_TEST]; + +static int test_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct rtc_test_data *rtd = dev_get_drvdata(dev); + time64_t alarm; + + alarm = (rtd->alarm.expires - jiffies) / HZ; + alarm += ktime_get_real_seconds() + rtd->offset; + + rtc_time64_to_tm(alarm, &alrm->time); + alrm->enabled = rtd->alarm_en; + + return 0; +} + +static int test_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct rtc_test_data *rtd = dev_get_drvdata(dev); + ktime_t timeout; + u64 expires; + + timeout = rtc_tm_to_time64(&alrm->time) - ktime_get_real_seconds(); + timeout -= rtd->offset; + + timer_delete(&rtd->alarm); + + expires = jiffies + timeout * HZ; + if (expires > U32_MAX) + expires = U32_MAX; + + rtd->alarm.expires = expires; + + if (alrm->enabled) + add_timer(&rtd->alarm); + + rtd->alarm_en = alrm->enabled; + + return 0; +} + +static int test_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct rtc_test_data *rtd = dev_get_drvdata(dev); + + rtc_time64_to_tm(ktime_get_real_seconds() + rtd->offset, tm); + + return 0; +} + +static int test_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct rtc_test_data *rtd = dev_get_drvdata(dev); + + rtd->offset = rtc_tm_to_time64(tm) - ktime_get_real_seconds(); + + return 0; +} + +static int test_rtc_alarm_irq_enable(struct device *dev, unsigned int enable) +{ + struct rtc_test_data *rtd = dev_get_drvdata(dev); + + rtd->alarm_en = enable; + if (enable) + add_timer(&rtd->alarm); + else + timer_delete(&rtd->alarm); + + return 0; +} + +static const struct rtc_class_ops test_rtc_ops_noalm = { + .read_time = test_rtc_read_time, + .set_time = test_rtc_set_time, + .alarm_irq_enable = test_rtc_alarm_irq_enable, +}; + +static const struct rtc_class_ops test_rtc_ops = { + .read_time = test_rtc_read_time, + .set_time = test_rtc_set_time, + .read_alarm = test_rtc_read_alarm, + .set_alarm = test_rtc_set_alarm, + .alarm_irq_enable = test_rtc_alarm_irq_enable, +}; + +static void test_rtc_alarm_handler(struct timer_list *t) +{ + struct rtc_test_data *rtd = timer_container_of(rtd, t, alarm); + + rtc_update_irq(rtd->rtc, 1, RTC_AF | RTC_IRQF); +} + +static int test_probe(struct platform_device *plat_dev) +{ + struct rtc_test_data *rtd; + + rtd = devm_kzalloc(&plat_dev->dev, sizeof(*rtd), GFP_KERNEL); + if (!rtd) + return -ENOMEM; + + platform_set_drvdata(plat_dev, rtd); + + rtd->rtc = devm_rtc_allocate_device(&plat_dev->dev); + if (IS_ERR(rtd->rtc)) + return PTR_ERR(rtd->rtc); + + switch (plat_dev->id) { + case 0: + rtd->rtc->ops = &test_rtc_ops_noalm; + break; + default: + rtd->rtc->ops = &test_rtc_ops; + device_init_wakeup(&plat_dev->dev, true); + } + + timer_setup(&rtd->alarm, test_rtc_alarm_handler, 0); + rtd->alarm.expires = 0; + + return devm_rtc_register_device(rtd->rtc); +} + +static struct platform_driver test_driver = { + .probe = test_probe, + .driver = { + .name = "rtc-test", + }, +}; + +static int __init test_init(void) +{ + int i, err; + + err = platform_driver_register(&test_driver); + if (err) + return err; + + err = -ENOMEM; + for (i = 0; i < MAX_RTC_TEST; i++) { + pdev[i] = platform_device_alloc("rtc-test", i); + if (!pdev[i]) + goto exit_free_mem; + } + + for (i = 0; i < MAX_RTC_TEST; i++) { + err = platform_device_add(pdev[i]); + if (err) + goto exit_device_del; + } + + return 0; + +exit_device_del: + for (; i > 0; i--) + platform_device_del(pdev[i - 1]); + +exit_free_mem: + for (i = 0; i < MAX_RTC_TEST; i++) + platform_device_put(pdev[i]); + + platform_driver_unregister(&test_driver); + return err; +} + +static void __exit test_exit(void) +{ + int i; + + for (i = 0; i < MAX_RTC_TEST; i++) + platform_device_unregister(pdev[i]); + + platform_driver_unregister(&test_driver); +} + +MODULE_AUTHOR("Alessandro Zummo "); +MODULE_DESCRIPTION("RTC test driver/device"); +MODULE_LICENSE("GPL v2"); + +module_init(test_init); +module_exit(test_exit); -- cgit v1.3.1